The present invention relates to boring or augering apparatus and, more particularly, to a hydraulically operated augering apparatus for attachment to the boom of a backhoe or the like.
For the purposes of digging trenches and other earth excavation, it is common practice to employ a so-called backhoe which is a hydraulically powered implement mounted to the rear of a tractor or similar machine and having an articulated boom extending rearward from the tractor, with the distal end of the boom being hydraulically positionable in azimuth, elevation and reach from the tractor and having a scoop mounted at the distal end for convenient trenching or other excavation while the tractor remains in the same stationary location. The articulated boom configuration of a backhoe facilitates trenching and other similar excavation by permitting the backhoe scoop to reach down into an excavation and the articulated boom arrangement readily facilitates reaching over the lip of an excavation area. In such excavation, it is frequently desirable to bore or auger into the face of the excavated surface, e.g. for the purpose of placing pipe under a pavement or other area adjacent the excavation. Thus, it is not unusual to excavate adjacent a pavement where it is desirable then to bore or auger beneath the pavement in order to avoid trenching or otherwise disrupting the surface of the pavement.
Heretofore, apparatus has been disclosed for use with a backhoe for such purpose. For example, Hamrick U.S. Pat. No. 2,969,844 discloses an earth boring implement particularly for use with a backhoe having an auger drive assembly comprising a drive shaft rotatably secured to a frame, the frame having frame members which extend transversely of the earth boring implement between the side walls of the scoop, such frame members being bolted to the sides of the scoop. The drive assembly thus has a shaft which is rotatable about an axis which extends out from the scoop of the backhoe, the arrangement being such that the axis is pivotable in a vertical plane and, more specifically, is permitted to pivot in the plane of articulation of the boom members. The drive assembly is rotated by a hydraulic motor by means of a chain and sprocket arrangement connecting the hydraulic motor to a sprocket which rotates the shaft to which an auger is secured. The Hamrick implement thereby permits boring by means of an auger or drill bit, but with the axis of the bit always remaining in the plane of articulation of the boom member. Since boring may not be carried out by such apparatus at an angle to the plane of articulation of the boom members, the apparatus is extremely limited in utility owing to the inability to locate the drill bit or auger axis at any angle different from the plane of articulation of the boom members.
To illustrate the difficulty inherent in such limitation, one may appreciate that it is often desired to auger into the face which terminates a trench excavation. While the Hamrick earth boring implement could be utilized for boring into the face at the end of a trench excavation, it would require that the tractor be located so that it is substantially in line with the axis of the trench. This is difficult and frequently impossible, owing to geographic limitations, the presence of buildings, or various other factors which must be taken into consideration in locating a tractor in a stable and secure location for the excavation. For example, if the trench is adjacent to a pavement and extends along said pavement but spaced therefrom by distance, it would be desirable to locate the tractor upon the pavement in order to avoid having the heavily laden rear wheels thereof on the soft earth adjacent the trench. In this instance, it would be impossible with the Hamrick implement to drill along the axis of the excavation. Moreover, the Hamrick apparatus would not permit boring to be accomplished into an excavation face which is facing toward the tractor, inasmuch as the boring implement may only be moved through a limited arcuate extent within the plane of articulation and, at either arcuate extent, is then limited by the degree of tipping movement permitted by the backhoe apparatus. A further disadvantage inherent in the Hamrick configuration is that the auger is not permitted to swing in a lateral axis since it is secured by the above noted frame arrangement to the sides of the bucket. Hence, any lateral movement of the auger would impose great strain upon the backhoe with the possibility of consequent damage thereto.
A vehicle mounted hole driller is disclosed by Furuseth U.S. Pat. No. 3,327,789. The apparatus disclosed in this patent has an earth auger universally mounted in depending relation to one side of the center of a tractor-carried frame, such as the frame of a fork loader or the like. Such apparatus is useful chiefly for post hole drilling and other drilling of primarily vertical holes in earth. The Furuseth apparatus is not useful for drilling into the face of an excavation at various depths and angles, inasmuch as it is incapable of reaching down into an excavation as a backhoe is capable of doing.
An earth boring machine is also disclosed by Von Ruden U.S. Pat. No. 3,563,320. Such machine has an auger for boring down into the earth adjacent the machine. The auger can be tilted at various angles relative to the vertical, but such machine is not useful for reaching down into an excavation and does not permit boring of a hole at various angles into the face of an excavation for such reason.
Wieger et. al. U.S. Pat. No. 3,460,691 discloses a telescopic dredge having a boom which may be oriented at various angles for reaching down into an excavation. Various tools can be mounted to the end of the boom, including an auger. However, the construction is apparently incapable of permitting orientation of the auger at various angles for drilling into various faces of the excavation and appears to be limited to a capability of drilling along an axis coaxial with the boom. Hence, its capability is even more limited than the earth boring implement of the above identified Hamrick patent.
Various excavation apparatus is taught by the prior art having pivots and swivels for facilitating the orientation of a tool, but none is known which provides for the fitting of a hydraulic boring unit to a hydraulic backhoe so as to provide full swivel in both horizontal and vertical planes and orientation of the drill in various positions other than vertical and other than in the plane of articulation of the boom members of the backhoe. Moreover, none of the prior art arrangements are such as effectively to utilize the augering force for inherent self-centering of the auger so as to prevent misalignment of augering.
The present invention overcomes these and other limitations of the prior art constructions.
An object of the present invention is to provide an improved augering apparatus for attachment to the boom of a machine for earth excavation, and particularly to provide such an augering apparatus which is specially adapted for convenient attachment to the hydraulically operated boom of a tractor-mounted backhoe or the like.
A further object of the invention is the provision of such apparatus which is intended to replace the scoop, i.e. bucket, of a backbone and is amenable to securement to the boom of the backhoe by the same means which conventionally secures such scoop to the backhoe.
Another object of the invention is the provision of such augering apparatus which is adapted for securement to the boom of a hydraulic backhoe in such manner as to provide full swiveling and pivoting in both horizontal and vertical planes and which permits the orientation of the drill in various positions so that the axis of rotation thereof may be oriented as desired, including orientation at an angle to the plane of articulation of the boom, whereby drilling is not limited only to the plane in which the boom of the backhoe moves normally.
A related object is the provision of such augering apparatus having swivel and pivot features allowing the unit to swivel to more than 180.degree. in a vertical plane and permitting the auger axis to be positioned through 360.degree. in the horizontal plane.
A still further object of the invention is the provision of such apparatus which is such as to provide for the avoidance of bending stress on the auger and the backhoe boom, and particularly such a configuration as provides a self-centering characteristic in response to augering thrust forces so as to avoid misalignment of the auger.
Yet another object of the invention is the provision of such augering apparatus which is hydraulically powered by means of a hydraulic motor for rotation of the auger, and the provision of such apparatus providing for proportioning of pressure of hydraulic fluid between the boom and the hydraulic motor for advantageous control selection of control effectiveness for positioning of the boom while augering is being carried out by the apparatus.
A related object of the invention is the provision of such hydraulically powered augering apparatus which provides hydraulic fluid for operation of such motor by means of flexible hydraulic lines which are connected in such a way as to avoid bending stress upon the hydraulic lines and damage thereto during augering.
Other objects of the invention include the provision of such augering apparatus which greatly facilitates the removal and installation of an auger from the augering apparatus while the apparatus is secured to the boom of a backhoe, the provision of such apparatus which is relatively simple, strong, durable and economical to manufacture.
Other objects and features will be apparent or pointed out hereinbelow in the following description.